If we're talking in a legal sense, flawlessly impersonating another person in the way the Chameleon does is so outside the scope of our reality that it's hard to match it with current laws. Realistically, she would probably feel like that if she found out (which she won't), but fiction involving shapeshifters rarely delves into that sort of thing, preferring to just let shapeshifter stories like this get played for humour (though it can also be played for horror/drama; see Abby Arcane). I remember how the JLU episode where Flash ends up in Lex's body and then is implied to have romanced Tala (though she was the one making the moves there) generated a bunch of discussions about whether that made the Flash technically a rapist; it's probably one of those storytelling conceits that should be left alone.
A reviewer (IGN, I think) had a good analysis of this issue, in that it uses Chameleon's impersonation to frame the things Peter isn't as a result either of being Spider-Man or just his personality: Fake-Peter is punctual, as MJ notes; he insults Flash; he's reasonably good at recognizing attraction and seducing women, etc.